Apparatus for grinding



, Nov. 13, 1934. A. F. MOUL APPARATUS FOR GRINDING Filed Aug. 4, 1933 v 2 Sheets-Sheet Iwvzwrmy ARTHUR F. M OUL Nov. 13, 1934. A. F. MOUL APPARATUS FOR GRINDING Filed Aug. 4, 1933 2 Sheets-Sheet Patented Nov. 13, I934 UNITED STATES PATENT OFFICE 1,980,872 APPARATUS FOR GRINDING Arthur F. Moul, Buffalo, N. Y., assignor to Samuei 0. Rogers & Company, Buffalo, N. Y., a corporation of New York Application August 4, 1933, Serial No. 683,617 4 Claims. (01. 51-122) My invention relates in general to a method 11 of the machine upon which the carriage 12 is of and apparatus for grinding, and in particular reciprocally mounted. The bed when designed to the grinding of edged tools, such, for instance, for sharpening long knives is necessarily of conas long relatively thin straight-edged knives. siderable length and it is preferably supported at It iswell known to those skilled in the art that each of its overhanging ends by means of a there is a difference of opinion in the grinding standard 15 which rests upon the floor supporting of a straight knife edge as to whether best results the machine and which is provided in its upper are derived by grinding toward the edge or away end with an adjusting screw 16 which engages from the edge of the tool being sharpened. I the bottom surface of the bed.

10 have discovered, however, that by my invention The bed 11 is provided with a bearing surface" much superior results are obtained when the 17 for bearing contact with a. bearing surface 18 workpiece is acted upon in both of these ways, formed on the downwardly projecting leg 19 of the grinding operation being preferably alterthe carriage 12. The bed is provided with an nately toward the edge during one stroke of the offset portion 20 formed on its upper surface 15 workpiece across the face of the grinding wheel, with a V-shaped bearing 21 upon which the carand away from the edge on the next stroke of riage 12 rests, the under surface of the carriage the tool. Such alternate action upon the outbeing provided with a corresponding groove for ting edge of the tool produces a smoother edge engagement with the V-shaped bearing. The than can be produced by grinding continuously bearing surface 17 and the V-shaped bearing sur- 20 in either of the manners above described. face 21 thereby provide ways for the carriage to One of the principal objects of my invention guide and support it during its reciprocal movehas been to provide a method whereby a smooth ment. unbroken edge may be ground upon a straight Arranged at the side of the housing 10 which edged tool. is opposite the bed 11 is a motor support 25 25 Another object of my invention has been to' upon which is mounted the electric motor 26 of provide a grinding machine in which the direcmy device. The shaft 27 of this motor extends 7 tion of rotation of the grinding wheel shall be forwardly toward the bed 11 of the machine and reversed each time the direction of travel of the upon its forward end is mounted the grinding knife or tool carriageis reversed. wheel 28. This grinding wheel is preferably of 30 Another object has been to provide means for cup shape and its grinding face is arranged at accomplishing the above results in a practical, a slight angle to the bed (in well known manner) simple and durable manner. so that the grinding operation is confined to one Moreover, my device is of such design that it side of the face of the wheel. The motor shaft can be inexpensively manufactured. 27 carries a pulley 30 which is connected to a '36 The above objects and advantages have been similar pulley 31 carried by a'drive shaft 32.

accomplished by the device shown in the accom- This drive shaft is mounted within the housing panying drawings, where I show one form of 10 in a suitable manner and its inner end enters apparatus for carrying out my method. In the a gear casing 33. Within this casing is a drive drawings: gear worm 34. which meshes with a worm wheel to Fig. 1 is a front elevation of my complete de- 35. This worm wheel is mounted upon a vertical vice. shaft 36 which has its lower end supported in Fig. 2 is an enlarged, fragmentary, transverse, the gear casing and its upper end projected sectional view, taken on line 2-2 of Fig. 1. through the housing 10. At the upper end of the Fig. 3 is a fragmentary, transverse, sectional vertical shaft 36 there is provided a drive pinion 45 view, taken on line 3-3 of Fig. 1. 37. This pinion meshes with a gear rack 38 Fig. 4 is a fragmentary, plan view, shog which is attached to the carriage 12 and preferthe reversing switch. ably secured to the outer face at the lower edge Fig. 5 is an enlarged, fragmentary, sectional of the leg 19 thereof. A belt 39 serves to connect view, showing a part of the feed mechanism. the pulleys 30 and 31. The carriage drive shaft to Fig. 6 is a fragmentary, plan view of the feed 32 extends outwardly through the front wall of cam and its supporting rod. the housing 10 where it is provided with a pulley Figs. '7 and 8 are diagrtic views showing 40, to be hereinafter described. the grinding operations during alternate cycles. Mounted upon the carriage 12 is a knife sup- The device shown in the accompanying drawport 45. This support is preferably provided at .55 ings comprisesahousing 10 which carries the bed each end with a suitable trunnion 46 which is adjustably mounted within a feed slide 47 so that its angle may be changed with respect to the face of the grinding Wheel so as to accommodate the support to the angle of the cutting edge of the blade being sharpened. In Fig. 2 one type of workpiece or knife blade being acted upon is shown at 48 and one type of clamp 49 suitable for this type of blade is shown. Obviously, as

is well known to those skilled in the art, the

clamping means employed will differ with the type of blade being sharpened, as, for instance,

' when a very thin blade is being ground, then a desired number, depending upon the length of the carriage, are mounted upon the carriage in such manner that they can be moved in a direction laterally to the carriage and each is provided. along its lower opposite edges with V- shaped surfaces 55 which engage with bearing way' strips 56. Each of the feed slides is arranged to receive a feed screw 57 which'is rotatably carried by a feed bracket 58. The feed screw is provided with a collar 59 for engagement with the bracket 58 and on the outer end of the screw it is provided with a worm wheel 60. A feed shaft 61 extends longitudinally across the rear of the machine and carries a feed worm 62 for each, of the worm wheels 60. The feed shaft 61 I is rotatably carried by suitable bearing brackets 63 which are attached to and supported by the carriage 12.

'Also at the rear of the machine and arranged beneath the feed shaft 61 is a feed cam 65. This cam is adjustably mounted upon a feed cam rod 66 which is supported by suitable brackets 67 carried by the housing 10. The feed cam is of obtuse V-shape, having angularly arranged surfaces 68 which engage with the lower end 69 of a feed lever 70 This feed lever is rotatably mounted upon the feed shaft 61 and has an upwardly extending arm 71. This arm carries a ratchet pawl 72 which engages the teeth of a ratchet wheel 73 which is rigidly carried by the feed shaft 61. A stop 74 is secured to the carriage 12 and extends forwardly so as to contact with the upwardly extending arm 71 of the feed lever so as to limit its movement in one direction and keeps its lower end in registering position with the inclined surface 68 of the feed cam. A helical spring 75 is provided which keeps the arm 74 of the lever in contact with the stop when the feed cam is not acting upon the lever.

Arranged under the grinding wheel 28 is a movable water trough 80. -This trough is carried 1 by suitable brackets 81 and is secured thereby to-the forward face of the leg 19 of the carriage 12. This pan is provided near its central portion with an outlet opening 82. Under the movable pan is a stationary water pan 83. This pan is suitably secured to the housing 10 or stationary parts of the device and is of such a length that it extends beyond the points of extreme movement of the outlet opening 82 of the movable pan 80. As shown in Fig. 3, the stationary pan 83 is provided with an outlet spout 84 which directs the water in the pan to the water tank 85 secured within the housing 10. This water tank Loa ers acts as a reservoir and within it is mounted a centrifugal pump 86 of any suitable type'which has its inlet opening (not shown) submerged in the water and has an outlet pipe 87 carried by its outlet opening (not shown). A flexible hose connection 88 connects the outlet 87 of the pump with a water supply tube 89. This tube is carried by a bracket-90 which is supported by the grinding wheel shield 91, and its lower end extends downwardly and directs water coming through it to. the surface of the tool which is being acted upon by the grinding wheel. The Water which flows over this surface being treated is caught in the movable pan 80 and flows out through its outlet opening 82 to the stationary pan and thence back to the water tank through the spout 84. The pump 86 is provided with a shaft 92 which has a pulley 93 on its outer end. This pulley is connected to the pulley 40 carried by the drive shaft 32 by means of a belt 94.

Supported in a convenient place within the housing 10 is a reversing switch 95 for reversing the electric current supplied to the electric motor 26. This switch has an operating arm 96 and this arm is so located that it is in the path of operating lugs 97. One of these lugs is shown in Figs. 2 and 4, and they are preferably carried by some portion of the carriage 12. For. convenience of illustration in Fig. 4 the lug 97 is shown as being carried by the stationary water pan 80, shown in dot and dash lines. These lugs engage with the arm 96 of the reverse switch at the extreme end of the movement in either direction of the carriage and first of all out 01f the current to the motor and then reverse the direction of the current through the motor so that its direction of rotation. is reversed. This reverse switch is a standard article of manufacture and its constructional details will not, therefore, be shown or described. Another article of standard manufacture is a switch box 98 which contains the electric switches, relays and other electric equipment necessary for the operation and reversal of the motor. This also is not shown or described in detail. Carried by the switch box 98 is preferably a timing switch 99 which is also a standard article of manufacture and by which the supply of current to the motor may be so controlled that the time of grinding any particular workpiece maybe predetermined by the workman so that the motor will automatically be stopped when the grinding'operation is finished. For clearness of illustration, the leads and conduits from the reverse switch to the motor and to the switch box have been'omitted.

From the foregoing and also from Figs. 7 and 8 it is obvious that when as shown in Fig. 7 the carriage is traveling to theleft, the wheel will be rotated ina clockwise direction and when the carriage is traveling to the-right (see Fig. 8) the wheel will be rotated in a counterclockwise direction. This brings about the alternategrinding action first toward the edge, as shown in Fig. 7, and then away from' the edge, as shown in Fig. 8. Obviously, each time the direction of rotation of the motor 26 is reversed, the carriage drive shaft 32 will be reversed and the carriage will thus be reciprocated backwardly and forwardly by such reversal without the addition of any reversing mechanism. The water pump 86 is of such a nature that it operates to pump water when rotating in either direction.

Obviously, when the carriage 12 gets to the limit of its stroke, one of the operating lugs 97 will engage with the arm 96 of the reverse switch .and then started again in the reverse direction whereupon the carriage will be operated to the other extreme end of its movement while the tool is being acted upon in a direction opposite to that of the previous stroke. The cutting edge of the blade is thus alternately acted upon by first grinding away from the edge and then toward the edge, which alternate grinding action produces a smooth cutting edge upon the tool being sharpened. As the carriage reaches the end of its stroke in one direction, the downwardly extending arm 69 of the feed lever will engage the inclined surface 68 of the feed cam 65 and cause it to be oscillated (as viewed in Fig. 5 in a counterclockwise direction) an amount depending upon the position of the'feed cam with respect to the arm 69. When oscillated, the feed lever will carry the ratchet around with it and serve to rotate the ratchet wheel 73 an amount depending upon the amount of movement of the feed lever. This amount of rotation is, of course. transmitted through the feed shaft 61 to the feed worms 62 and worm wheels 60 and through them to the adjusting screws 57 carried by the worm wheels and thus move the feed slides a predetermined amount toward the wheels so as to produce a fresh out;

Obviously, some modifications of the details herein shown and described may be made without departing from the spirit of my invention or the scope of the appended claims, and I do not, therefore, wish to be limited to the exact embodiment herein shown and described, the form shown being merely a preferred embodiment thereof.

Having thus described my invention, what I claim is: I

1. A grinding machine comprising a housing, a bed carried by the housing, a carriage slidably mounted upon the bed, a knife support mounted upon the carriage, a motor carried by the housing and arranged opposite the knife support, means connecting the motor with the carriage for reciprocating the same, a grinding wheel carried by the motor, the working face of said grinding wheel being arranged at such an angle with respect to the knife edge that only a segmental portion of its working face at one side of a vertical plane passing through the axis of the wheel is brought into grinding engagement with.v such edge at any one time, and means actuated at the end of eachstroke of the carriage for causing the wheel to grind the full length of the bevel of the knife toward its cutting edge and then to grind the full length of the bevel away from its cutting edge.

N 2. A grinding machine comprising a housing,

a bed carried by the housing, a carriage slidably.

mounted upon the bed, a knife support mounted upon the carriage, a motor carried by the housing and arranged opposite the knife support, means connecting the motor with the carriage for reciprocating the same, a grinding wheel carried by the motor, the working face of said grinding wheel being arranged at such an angle with respect to the knife edge that only a segmental I portion of its working face at one side of a vertical plane passing through the axis of the wheel is brought into grinding engagement with such edge at any one time, and means actuated at the end of each stroke of the carriage for reversing the direction of rotation of the wheel.

3. A grinding machine comprising a reciprocating .km'fe support, a grinding wheel suitably mounted opposite the knife support, the working face of said grinding wheel being arranged at such an angle with respect to the knife edge that only a segmental portion of its working surface at one side of a vertical plane passing through the axis ,,of the wheel is brought into grinding engagement with such edge at any one time, means for feeding the knife support toward the grinding wheel, and means actuated at the end of each stroke of the carriage for reversing the rotation of the grinding wheel.

4. In a grinding machine, the combination with a reciprocating knife support and a grinding wheel rotatably mounted opposite the support, of means for reciprocating the support, the working face of the grinding wheel being arranged at such an angle with respect to the knife edge that only a segmental portion of its working face at one side of a vertical plane passing through the axis of the wheel is brought into grinding engagement with such edge at any one time, and means for reversing the direction of rotation of the wheel each time the direction of reciprocation of the support is changed.

ARTHUR F. MOUL. 

